A 45,X male with Y-specific DNA translocated onto chromosome 15.

A 20-year-old male patient with chromosomal constitution 45,X, testes and normal external genitalia was examined. Neither mosaicism nor a structurally aberrant Y chromosome was observed when routine cytogenetic analysis was performed on both lymphocytes and skin fibroblasts. Y chromosome-specific single-copy and repeated DNA sequences were detected in the patient's genome by means of 11 different recombinant-DNA probes of known regional assignment on the human Y chromosome. Data indicated that the short arm, the centromere, and part of the long-arm euchromatin of the Y chromosome have been retained and that the patient lacks deletion intervals 6 and 7 of Yq. High-resolution analysis of prometaphase chromosomes revealed additional euchromatic material on the short arm of one of the patient's chromosomes 15. After in situ hybridization with the Y chromosome-specific probe pDP105, a significant grain accumulation was observed distal to 15p11.2, suggesting a Y/15 chromosomal translocation. We conclude that some 45,X males originate from Y-chromosome/autosome translocations following a break in the proximal long arm of the Y chromosome.     

Evolution of the secondary haustoria to a primary haustorium in the parasiticScrophulariaceae/Orobanchaceae

In the parasiticScrophulariaceae andOrobanchaceae, two types of contact organs exist: secondary and primary haustoria. Secondary haustoria are lateral organs, developing in large numbers and only when the seedling is fully established. In contrast, a primary haustorium represents the first developmental stage of the seedling itself. In the root system of the parasiticLesquereuxia syriaca (=Siphonostegia syriaca) there are only secondary haustoria, but a few of them apparently develop in a terminal position. This is achieved by transferring the haustorial initiation region closer to the root apex. One can interpret this as a transformation of the apical meristem into a meristematic haustorial tissue. On the condition that an extreme shortening (abbrevation) of the primary root could happen, we discuss the transformation of the terminal secondary into a primary haustorium.     

Cloning and characterization of keratin D,a murine endodermal cytoskeletal protein induced during in vitro differentiation of F9 teratocarcinoma cells

Summary We have identified a cDNA coding for the murine keratin D from a collection of clones representing F9 teratocarcinoma stem cell mRNA sequences. These sequences are synthesized specifically after the addition of retinoic acid and cAMP to the culture medium. The clone is 1,382 nucleotides long and contains the entire information for the active polypeptide, the complete 3 end and most, if not all, of the 5 non-coding region. The mRNA is found in hepatocytes, in PYS-2 cells (an endodermal cell line) and in differentiated (retinoic-acid-treated) F9 cells, but not in untreated F9 cells. The length of the mRNA is 1.4 kb, as estimated by Northern blot hybridization. Southern hybridization performed under very stringent conditions detects a single fragment hybridizing strongly with the cloned cDNA, suggesting that the mouse genome contains only one or very few copies of this gene. We present the first complete sequence of a keratin expressed in simple epithelia, i.e. keratin D, and discuss its structural features.     

Functional differences between small and large luteal cells of the late-pregnant vs. nonpregnant cow

This paper describes an in vitro model for the study of two types of steroidogenic luteal cells from cows in different physiological states. Two different populations of enzymatically dispersed bovine luteal cells were separated on the basis of size in a Cel-Sep Sedimentation Chamber. The separated small (12.5-23 micron in diameter) and large (greater than 23 micron in diameter) luteal cells of late-pregnant cows (Days 190-280) contained the distinct morphological characteristics previously defined for these two populations of cells. Cells were evaluated for progesterone (P4) production during a 3-h incubation with and without bovine luteinizing hormone (bLH, 10 ng/ml). Both small and large luteal cells from the late-pregnant cow were found to contain equal levels of P4 at Time 0 and increased but equal levels of P4 after a 3-h incubation. Neither cell type showed an increase in P4 production in response to the addition of bLH (p greater than 0.05). Since these results differed from earlier reports for luteal cells of the nonpregnant cow, small and large luteal cells of the mid-cycle (Day 14) were incubated, and the levels of P4 production were compared with P4 levels from the late pregnant cow. In agreement with previous reports for nonpregnant cows, progesterone content at Time 0 was 7-fold higher in large cells than in small cells (p less than 0.05), and after 3 h of incubation, 13-fold higher (p less than 0.05). Although the small cells responded to the presence of bLH in the incubation medium with a 4-fold increase in P4 production, this increase was not significant (p greater than 0.05). The large cell did not respond to bLH. However, the large cell type continued to contain and produce more P4 than did the small cells treated with bLH. This study indicates that both the small and large luteal cells of late-pregnancy are able to produce P4. However, the large luteal cell of the estrous cycle produces greater quantities of P4 than does the small luteal cell or the large luteal cell of late pregnancy.     

Biological membrane modeling with a liquid/liquid interface. Probing mobility and environment with total internal reflection excited fluorescence.

Total internal reflection of exciting light, in combination with fluorescence intensity and polarization measurements, was used to selectively study fluorescent compounds adsorbed to the interface region between two immiscible liquids. A fluorometer was constructed which provided excitation at variable angles of incidence and allowed sensitive detection of polarized fluorescence emitted from the interface. The compound 4,4'-bis-1-phenylamino-8-naphthalenesulfonate (bis-ANS) was examined at a decalin/water interface and was found to possess remarkable affinity for the interface region with the bulk of the adsorbed molecule residing in the decalin phase. The adsorbed fluorophore displayed an apparent hindered rotation in the plane of the interface with a rotational diffusion coefficient 3- to 12-fold lower than that expected for bis-ANS in solution. While other dyes examined were not found to be significantly surface active, the addition of cationic surfactant sufficed to induce adsorption of the anionic fluorophore 1-aminonaphthalene-3,6,8-trisulfonic acid. This fluoropore was found to reside in an aqueous environment when bound to the interface, and it also exhibited hindered rotation in the plane of the interface. As the concentrations of the dyes were increased, both adsorbed dyes exhibited polarization reductions consistent with excitation energy transfer. Adsorption of bis-ANS was reversed by addition of bovine serum albumin. The membrane protein cytochrome b5 was found not to bind at the decalin/water interface, indicating that interaction with lipid is required for its adherence to biological membranes.     

The white gene as a marker in a new P-element vector for gene transfer in Drosophila.

We describe new vectors suitable for P-element mediated germ line transformation of Drosophila melanogaster using passenger genes whose expression does not result in a readily detectable phenotypic change of the transformed flies. The P-element vectors contain the white gene fused to the heat shock protein 70 (hsp70) gene promoter. Expression of the white gene rescues the white phenotype of recipient flies partly or completely even without heat treatment. Transformed descendents of most founder animals (GO) fall into two classes which are distinguishable by their orange and red eye colours. The different levels of white expression are presumably due to position effects associated with different chromosomal sites of insertion. Doubling of the gene dose in orange eyed fly stocks results in an easily visible darkening of the eye colour. Consequently, the generation of homozygous transformants is easily possible by simple inbreeding due to the phenotypic distinction of homo- and heterozygous transformants. Cloning into these P-element vectors is facilitated by the presence of polylinkers with 8 and 12 unique restriction sites.     

Ultrastructural changes in maturing pollen grains ofApium nodiflorum L. (Apiaceae), with special reference to the endoplasmic reticulum

Summary The ultrastructural events in 3-cellular pollen grains ofApium nodiflorum L. are investigated during pollen maturation. Three distinct developmental stages are distinguished from the formation of sperm cells up to anthesis, whereby the rough endoplasmic reticulum (RER) is mainly involved. The most conspicious form is the highly dilated RER in the vegetative cytoplasm of the youngest pollen grains, which changes to vesicular RER in the following stage. In mature pollen grains the RER has a narrow cisternal configuration and often forms stacks. Pollen activation is preceded by the accumulation of polysaccharide particles.     

Tool use in capuchin monkeys: Distinguishing between performing and understanding

A horizontal plexiglas tube containing a food-reward was presented to four naive tufted capuchins and suitable sticks were provided to push the reward out. Three monkeys out of four spontaneously used the tools and showed very different styles of solving the task. In more complex conditions, in which the sticks needed to be combined or actively modified in order to become effective, the monkeys were always successful; however, their performance was loaded with errors which did not disappear throughout the trials. Evidence of a difference between success in solving the problem and its understanding was found. This suggests that although capuchins can discover new means through active experimentation, they do not mentally represent the characteristics necessary for a tool to be effective, nor do they modify the tool appropriately beforehand. At this level, a major difference with chimpanzees emerges.